Post-Settlement Erosion and Deposition

This resource received an Accept or Accept with minor revisions rating from a Panel Peer Review process

These materials were reviewed using face-to-face NSF-style review panel of
geoscience and geoscience education experts to review groups of resources addressing
a single theme. Panelists wrote reviews that addressed the criteria:

scientific accuracy and currency

usability and

pedagogical effectiveness

Reviewers rated the resources:

Accept

Accept with minor revisions

Accept with major revisions, or

Reject.

They also singled out those resources they considered particularly exemplary, which are given a gold star rating.

Following the panel meetings, the conveners wrote summaries of the panel discussion for each resource; these were
transmitted to the creator, along with anonymous versions of the reviews.
Relatively few resources were accepted as is. In most cases, the majority of the resources were either designated as 1) Reject or 2) Accept with major revisions.
Resources were most often rejected for their lack of completeness to be used in a classroom or they contained scientific inaccuracies.

Summary

In this example, a field laboratory in introductory geology becomes a test of a hypothesis: Does the model proposed by Stanley Trimble for Coon Creek, Wisconsin adequately describe the history of post-European-settlement erosion and deposition in a small drainage in southeast Minnesota?

Learning Goals

This exercise includes the following pedagogical strategies:

working in groups

collecting new data in the field

collecting and working with quantitative data

close reading of a professional article and associated commentary and debate

writing a lab report in the format of a scientific article

Context for Use

A version of this exercise can be constructed for any area of the country where agriculture, grazing and/or urbanization has altered the landscape. See references at the end of the .pdf file to resources for the Pacific Northwest and desert Southwest.

Look for the following characteristics in choosing a field site:

An area that can be covered on foot in a single lab period (less than one km2)

A stream valley that has been partially filled with sediment and later incised, so that sedimentary features of the fill are visible

Teaching Notes and Tips

Teaching tips for this lab:

Many students will not read the Trimble paper carefully until after they return from the field. Thus, it is important to take time in the field to explain how their field measurements can be translated into volumes of material deposited and eroded.

You may want to divide the field site and have each small group of three students measure part of it. Each group's results could then be posted to the entire class.

Make a base map for the students from an air photo or topographic map. [Link to "How to find an air photo of your area?]

Assessment

From Geology 120 syllabus: "When reading written work, Mary looks for well-defined questions, good understanding of the subject, careful and complete observations of geologic processes, sound logic connecting the observations to the conclusions, clearly stated conclusions and complete discussion of the implications of the conclusions. All sources of information, including web sites, should be cited completely."
For this assignment specifically:

Does the paper have appropriate sections and subheadings?

Do each of the sections contain the appropriate content?

Are all three questions addressed in the discussion?

Are results reported accurately and clearly? Were enough measurements taken?

Does the paper show a reasonable level of understanding of the geological history and how humans may have influenced this history?

Can I tell from the paper that the students have read the Trimble article and its relatives?